Liberals can be disarming. In fact, they are for disarming anybody who can be disarmed, whether domestically or internationally.

Unfortunately, the people who are the easiest to disarm are the ones who are the most peaceful — and disarming them makes them vulnerable to those who are the least peaceful.

We are currently getting a painful demonstration of that in Ukraine. When Ukraine became an independent nation, it gave up all the nuclear missiles that were on its territory from the days when it had been part of the Soviet Union.

At that time, Ukraine had the third largest arsenal of nuclear weapons in the world. Do you think Putin would have attacked Ukraine if it still had those nuclear weapons?

Or do you think it is just a coincidence that nations with nuclear weapons don’t get invaded?

Among those who urged Ukraine to reduce even its conventional, non-nuclear weapons as well, was a new United States Senator named Barack Obama. He was all for disarmament then, and apparently even now as President of the United States. He has refused Ukraine’s request for weapons with which to defend itself.

As with so many things that liberals do, the disarmament crusade is judged by its good intentions, not by its actual consequences.

Indeed, many liberals seem unaware that the consequences could be anything other than what they hope for. That is why disarmament advocates are called “the peace movement.”

Whether disarmament has in fact led to peace, more often than military deterrence has, is something that could be argued on the basis of the facts of history — but it seldom is.

Liberals almost never talk about disarmament in terms of evidence of its consequences, whether they are discussing gun control at home or international disarmament agreements.

International disarmament agreements flourished between the two World Wars. Just a few years after the end of the First World War there were the Washington Naval Agreements of 1921-1922 that led to the United States actually sinking some of its own warships. Then there was the celebrated Kellogg-Briand Pact of 1928, in which nations renounced war, with France’s Foreign Minister Aristide Briand declaring, “Away with rifles, machine guns, and cannon!” The “international community” loved it.

In Britain, the Labour Party repeatedly voted against military armaments during most of the decade of the 1930s. A popular argument of the time was that Britain should disarm “as an example to others.”

Unfortunately, Hitler did not follow that example. He was busy building the most powerful military machine on the continent of Europe.

Nor did Germany or Japan allow the Washington Naval Agreements to cramp their style. The fact that Britain and America limited the size of their battleships simply meant that Germany and Japan had larger battleships when World War II began.

What is happening in Ukraine today is just a continuation of the old story about nations that disarm increasing the chances of being attacked by nations that do not disarm.

Any number of empirical studies about domestic gun control laws tell much the same story. Gun control advocates seldom, if ever, present hard evidence that gun crimes in general, or murder rates in particular, go down after gun control laws are passed or tightened.

That is the crucial question about gun control laws. But liberals settle that question by assumption.

Then they can turn their attention to denouncing the National Rifle Association.

But neither the National Rifle Association nor the Second Amendment is the crucial issue. If the hard facts show that gun control laws actually reduce the murder rate, we can repeal the Second Amendment, as other Amendments have been repealed.

If in fact tighter gun control laws reduced the murder rate, that would be the liberals’ ace of trumps. Why then do the liberals not play their ace of trumps, by showing us such hard facts? Because they don’t have any such hard facts. So they give us lofty rhetoric and outraged indignation instead.

Thomas Sowell is a senior fellow at the Hoover Institution, Stanford University, Stanford, CA 94305. His website is www.tsowell.com. To find out more about Thomas Sowell and read features by other Creators Syndicate columnists, visit www.creators.com.